Carman Mill Road, Merrick Road, Montauk Highway

Direction: East/West
Western Terminus: Sunrise Highway (NY 27) in Massapequa
Eastern Terminus: Sunrise Highway (NY 27) and Montauk Highway (Suffolk CR 85) in Oakdale
Distance: 17.31 miles
Counties: Nassau, Suffolk
Signed: Yes

NY 27A begins as Carman Mill Road at Sunrise Highway (NY 27), just west of the Nassau-Suffolk border. Carman Mill Road runs due south and ends at Merrick Road. NY 27A is then routed to the east along Merrick Road into Suffolk. In Copiague, Merrick Road becomes Montauk Highway. Montauk Highway is the southernmost east/west route in Suffolk County. In Oakdale, it meets Sunrise Highway (NY 27) and NY 27A ends. From this point east, Montauk Highway is designated CR 85 and CR 80. Before 1972, the NY 27A designation extended east along Montauk Highway to Southampton.